package common.service.util;

import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;

/**
 * @Description: AES加密
 * @author yuanliang
 * @date 2016年3月21日 下午4:49:36 
 */
public class AesUtil {

    private static final String AES = "AES";
    private static final String AES_KEY = "EPEP97532468qwer";//必须15位
//    private static final String CRYPT_KEY = "YUUAtestYUUAtest";

    /**
     * 加密
     * @param data
     * @return
     * @throws Exception
     */
    public final static String encrypt(String data) {
        try {
            return byte2hex(encrypt(data.getBytes(), AES_KEY));
        } catch (Exception e) {
        }
        return null;
    }

    /**
     * 解密
     * @param data
     * @return
     * @throws Exception
     */
    public final static String decrypt(String data) {
        try {
            return new String(decrypt(hex2byte(data.getBytes()), AES_KEY));
        } catch (Exception e) {
        }
        return null;
    }


    /**
     * 加密 字节数组
     * @param src
     * @param key
     * @return
     * @throws Exception
     */
    public static byte[] encrypt(byte[] src, String key) throws Exception {  
        Cipher cipher = Cipher.getInstance(AES);  
        SecretKeySpec securekey = new SecretKeySpec(key.getBytes(), AES);  
        cipher.init(Cipher.ENCRYPT_MODE, securekey);//设置密钥和加密形式  
        return cipher.doFinal(src);  
    }  
  
    /** 
     * 解密 字节数组
     * @param src
     * @param key
     * @return 
     * @throws Exception 
     */  
    public static byte[] decrypt(byte[] src, String key)  throws Exception  {  
        Cipher cipher = Cipher.getInstance(AES);  
        SecretKeySpec securekey = new SecretKeySpec(key.getBytes(), AES);//设置加密Key  
        cipher.init(Cipher.DECRYPT_MODE, securekey);//设置密钥和解密形式  
        return cipher.doFinal(src);  
    }  
      
    /** 
     * 二行制转十六进制字符串 
     *  
     * @param b 
     * @return 
     */  
    public static String byte2hex(byte[] b) {  
        String hs = "";  
        String stmp = "";  
        for (int n = 0; n < b.length; n++) {  
            stmp = (Integer.toHexString(b[n] & 0XFF));
            if (stmp.length() == 1)  
                hs = hs + "0" + stmp;  
            else  
                hs = hs + stmp;  
        }  
        return hs.toUpperCase();  
    }  
  
    public static byte[] hex2byte(byte[] b) {  
        if ((b.length % 2) != 0)  
            throw new IllegalArgumentException("长度不是偶数");  
        byte[] b2 = new byte[b.length / 2];  
        for (int n = 0; n < b.length; n += 2) {  
            String item = new String(b, n, 2);  
            b2[n / 2] = (byte) Integer.parseInt(item, 16);  
        }  
        return b2;  
    }  
      

      
}